Eye-opening analysis, which I can use to bolster my arguments to my kids against gift cards (*$s they can't stand). Thanks.
As far as the "free-coffee" counter-argument, the cost of coffee to *$s is a vanishingly small part of their overall costs or of what they charge you.
Why would any for-profit business have a program that reduces their profit or benefits you? This is similar as all those high cost warranties on electronics.